La Sinueuse is a Pink October running event held in Saint-Malo, on the Breton coast, offering 5 km and 10 km distances. It is organized by Sinoo, a local association supporting women with cancer, using the event to raise awareness for breast cancer. The race takes place alongside La Malouine, and the entire day is known as Tous en rose, or Everyone in Pink.
Participants start in the center of Paramé, a district of Saint-Malo, and follow the course through the city. The event attracts approximately 4,500 runners and can sell out, creating a strong community atmosphere rather than a small club event. Wearing pink is central to the day's identity, and supporters are encouraged along the route, with planned entertainment throughout the race.